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diff --git a/docs/configuration/system/ntp.rst b/docs/configuration/system/ntp.rst deleted file mode 100644 index 223447f5..00000000 --- a/docs/configuration/system/ntp.rst +++ /dev/null @@ -1,77 +0,0 @@ -.. _ntp: - -### -NTP -### - -:abbr:`NTP (Network Time Protocol`) is a networking protocol for clock -synchronization between computer systems over packet-switched, variable-latency -data networks. In operation since before 1985, NTP is one of the oldest Internet -protocols in current use. - -NTP is intended to synchronize all participating computers to within a few -milliseconds of :abbr:`UTC (Coordinated Universal Time)`. It uses the -intersection algorithm, a modified version of Marzullo's algorithm, to select -accurate time servers and is designed to mitigate the effects of variable -network latency. NTP can usually maintain time to within tens of milliseconds -over the public Internet, and can achieve better than one millisecond accuracy -in local area networks under ideal conditions. Asymmetric routes and network -congestion can cause errors of 100 ms or more. - -The protocol is usually described in terms of a client-server model, but can as -easily be used in peer-to-peer relationships where both peers consider the other -to be a potential time source. Implementations send and receive timestamps using -:abbr:`UDP (User Datagram Protocol)` on port number 123. - -NTP supplies a warning of any impending leap second adjustment, but no -information about local time zones or daylight saving time is transmitted. - -The current protocol is version 4 (NTPv4), which is a proposed standard as -documented in :rfc:`5905`. It is backward compatible with version 3, specified -in :rfc:`1305`. - -Configuration -============= - -.. cfgcmd:: set system ntp server <address> - - Configure one or more servers for synchronisation. Server name can be either - an IP address or :abbr:`FQDN (Fully Qualified Domain Name)`. - - There are 3 default NTP server set. You are able to change them. - - * ``0.pool.ntp.org`` - * ``1.pool.ntp.org`` - * ``2.pool.ntp.org`` - -.. cfgcmd:: set system ntp server <address> <noselect | pool | preempt | prefer> - - Configure one or more attributes to the given NTP server. - - * ``noselect`` marks the server as unused, except for display purposes. The - server is discarded by the selection algorithm. - - * ``pool`` mobilizes persistent client mode association with a number of - remote servers. - - * ``preempt`` a preemptable association is expendable. - - * ``prefer`` marks the server as preferred. All other things being equal, - this host will be chosen for synchronization among a set of correctly - operating hosts. - -.. cfgcmd:: set system ntp listen-address <address> - - NTP process will only listen on the specified IP address. You must specify - the `<address>` and optionally the permitted clients. Multiple listen - addresses can be configured. - -.. cfgcmd:: set system ntp allow-clients address <address> - - List of networks or client addresses permitted to contact this NTP server. - - Multiple networks can be configured. - -.. cfgcmd:: set system ntp vrf <name> - - Specify name of the :abbr:`VRF (Virtual Routing and Forwarding)` instance. |